How to place the GameObjects in a sequence on the plane

Hi, Unity heroes. I’m trying to place some gameObjects on a plane(in sequence). But I’m not able to place the Objects in proper position. I’m not able find the edge points of the plane(x,y,z). Please any one help me.

I think I understand your question?!

Can you not just use simple maths in your head?:

If you plane is 20 units width (x), and your cube is 1 unit width (x), then, to position it at the edge of the plane, you just move the cube 10 places on the x axis - the half size of the cube (0.5).

Formula: Cube Position X = PlaneScaleX / 2 - CubeScaleX / 2.

Also, you can hold down cmd to move snap your cube. Or V to snap to vertices.